The present invention relates to an apparatus for sensing the weight of an object in a vehicle seat and for controlling a restraint system in accordance with the weight of the object.
An apparatus for restraining an occupant of a vehicle seat typically includes seat belt webbing, a tongue on the webbing, and a seat belt buckle. An occupant weight sensor is mounted in the vehicle seat. The weight sensor provides an output signal which indicates a sensed weight of the occupant of the seat. The apparatus further includes an inflatable vehicle occupant protection device, such as an air bag, a source of inflation fluid for inflating the inflatable occupant protection device, and a controller.
When the vehicle experiences a crash, the source of inflation fluid is actuated by the controller and directs inflation fluid into the inflatable occupant protection device. The controller receives the output signal from the weight sensor in the seat and controls the amount of inflation fluid directed into the inflatable occupant protection device in response to the output signal from the weight sensor. If the weight sensed by the weight sensor is below a predetermined amount, i.e., a low weight in the seat or no occupant in the seat, then the controller disables the source of inflation fluid to prevent inflation of the inflatable occupant protection device. The controller thus controls the fluid pressure in the inflatable protection device and the restraining force provided by the inflatable protection device based on the sensed weight of the occupant. The controller may also disable the inflatable protection device.
In accordance with the present invention, an apparatus includes seat belt webbing for restraining an object, such as a vehicle occupant, in a vehicle seat. A sensor associated with the vehicle seat senses a sensed weight of the object in the vehicle seat. The sensed weight may differ from the actual weight of the object. A seat belt tension sensor senses the tension in the seat belt webbing. A controller determines a computed weight of the object as a function of both the sensed weight and the tension in the seat belt webbing.